LAB

SEME

IP5561C

Prelim. 4/95

SWITCHED–MODE

POWER SUPPLY

CONTROL CIRCUIT

FEATURES

• STABILISED POWER SUPPLY

• TEMPERATURE COMPENSATED REFERENCE

SOURCE

• SAWTOOTH GENERATOR

• PULSE WIDTH MODULATOR

• CURRENT LIMITING

• 8 PIN DIP

SUPPLY

Voltage Sourced

Current Sourced

OUTPUT TRANSISTOR

Output Current

Collector Voltage

(Pin 7)

Operating Junction Temperature

Storage Temperature Range

18V

30mA

40mA

18V

See Ordering Information

–55 to +150°C

TOP VIEW

J Package – 8 Pin Ceramic DIP

N Package – 8 Pin Plastic DIP

D Package – 8 Pin Plastic (150) SOIC

1

2

3

4

8

7

6

5

OUTPUT

FEEDBACK

GAIN

GND

CURRENT

SENSE

V

Z

V

CC

R

Part

J–Pack

N–Pack

D–8

Temp.

Number

8 Pin

8 Pin

8 Pin

Range

IP5561

-55 to +125°C

IP5561C

0 to +70°C

Order Information

Note:

To order, add the package identifier to the part number.

eg.

IP5561J

IP5561CD–8

GAIN

5

SAWTOOTH

GENERATOR

LATCH

S

R

0.5V

CURRENT

SENSE

6

STABILISED

SUPPLY

18

GND

2

4

3

CC

V

z

V

FEEDBACK

ERROR

AMP

PWM

T

C

T

R

REFERENCE

VOLTAGE

CC

V

OUTPUT

7

8.2V

BLOCK DIAGRAM

DESCRIPTION

The IP5561 is a control circuit for use in switched

mode power supplies. This single monolithic chip

incorporates all the control and supervisory (protection)

functions required in switched mode power supplies,

including an inter nal temperature compensated

reference source, internal zener reference, sawtooth

generator, pulse width modulator, output stage and

cycle by cycle current limit.